Embodiments of the invention generally relate to organic x-ray detectors. More particularly, embodiments of the invention relate to organic x-ray detectors including oxygen getter layers.
Digital x-ray detectors fabricated with continuous photodiodes have potential applications for low cost digital radiography as well as for rugged, light-weight and portable detectors. Digital x-ray detectors with continuous photodiodes have an increased fill factor and potentially higher quantum efficiency. The continuous photodiode generally includes organic photodiodes (OPDs). A scintillator which converts x-ray to visible light is generally disposed on top of the OPDs.
Typical organic x-ray detectors are subject to performance degradation upon exposure to oxygen. Possible degradation mechanisms include one or both of oxidation of electrode materials and oxidation of organic materials (e.g., OPD materials). During the post OPD deposition processes, such as, scintillator deposition, encapsulation, laser repair, or operation, OPD has a high chance of exposure to air. Most organic based photodiodes are sensitive to oxygen, and hence need to be protected from the oxygen-containing air.
In conventional packaging (for example in food industry), iron powder is commonly used as an oxygen scavenger. However, iron as an oxygen scavenger may be ineffective since the packaging typically also contains a desiccant, and the oxygen scavenging reaction requires moisture to be efficient. Non-ferrous oxygen scavengers may include cobalt-catalyzed polymers such as Nylon MXD6, which is used in multi-layer packaging. Thus, typical oxygen scavengers may have the disadvantages of being ineffective in anhydrous packaging or of releasing noxious products.
Therefore, there is a need for x-ray detector configurations with improved oxygen getter layers, thereby reducing the oxidation of OPD and/or electrodes.